FUEL CUT-OFF UNIT ATTACHMENT STRUCTURE

The present invention provides an attachment structure of a fuel cut-off unit (U) that is provided in a fuel tank () of a saddle-type vehicle (), includes a breather passage () for discharging volatile fuel to the outside, and includes a valve device () for cutting off outflow of liquid fuel. The fuel cut-off unit (U) includes an accommodation container () constituted of a fitting portion (U) which is inserted into the fuel tank () at the time of attachment to the fuel tank () and a unit exterior portion (U) which is positioned outside the fuel tank (). A first locking portion () for performing positioning at the time of attachment to the fuel tank () is formed in the fitting portion (U). A penetration hole (C) penetrating from the inside to the outside such that the fitting portion (U) is inserted therethrough is formed in the fuel tank (). A second locking portion (F) for fixing the fuel cut-off unit (U) by causing the first locking portion () to be engaged from an inner side of the fuel tank is provided in a circumferential edge portion of the penetration hole (C).